Creamy Vegetable Casserole with Crunchy Chex Topping Recipe

Name: My Grandma’s Thanksgiving Casserole Has a Crunchy, Buttery Topping You’ll Dream About
Prep time: 15 min
Cook time: 45 min
Total time: 60 min
Yield: 6
Ingredients: 4 tablespoons unsalted butter, plus more softened butter for greasing baking dish; 3 medium carrots, peeled; 6 ounces green beans, ends trimmed; 4 stalks celery plus 1 tablespoon finely chopped celery leaves; 3/4 cup water; 3/4 teaspoon salt; 1/4 teaspoon freshly ground black pepper; 1 teaspoon ground thyme, divided; 1 (10.5-ounce) can cream of mushroom soup; 3 cups Rice Chex cereal; 1/2 teaspoon onion powder

close-up view of Grandma's Creamy Vegetable Casserole with Crunchy Chex Topping in a baking dish — Simply Recipes / Frank Tiu

Every forkful of this nostalgic casserole offers a blend of creamy sauce and colorful, perfectly tender vegetables.
A topping of crushed Rice Chex cereal toasted in butter adds a craveable, crisp finish.
Partially steaming the vegetables with aromatics creates a homemade broth for deeper flavor.

It was sometime in the early 2000s, and I was sitting at the little bistro table in my grandma’s kitchen in wine country, the day before Thanksgiving. There wasn’t a chill in the air like I was used to in the Midwest, and I swear I could smell the California sunshine even through all the aromas of festive food preparations.

It was a special occasion to spend the holiday at my grandma’s house halfway across the country, and we were all busy preparing for a relatively big crowd that year. The kitchen was buzzing, everyone with a different task at hand.

At this point in time, I had never tasted my grandma’s signature vegetable casserole, since my mom tended to make green beans almondine. I remember my Uncle Kenny adamantly declaring that no one else was allowed to cut the vegetables for the casserole—only my grandma was allowed to do it.

To him, this casserole was so near and dear to his heart that it simply wouldn’t be the same if even the knife cuts were different than what he was used to. That’s when I knew this had to be something special.

My grandma was in her late 80s by this time, so standing up at the counter would have been too much. She sat next to me at that tiny little table and meticulously sliced carrots, celery, and green beans into pieces no bigger than maybe half an inch, and delicately tossed them into a saucepan to start the recipe. All these years later, I am so glad I watched and learned.

close-up view of Grandma's Creamy Vegetable Casserole with Crunchy Chex Topping on a plate with a fork — Simply Recipes / Frank Tiu

How to Make My Grandma’s Creamy Vegetable Casserole

As it turns out, my uncle wasn’t wrong. Slicing the vegetables to the correct size was one of the keys to success for this vegetable casserole. Making sure each of the elements is cut into pieces somewhere between a quarter and a half an inch ensures that they will cook evenly, and each forkful will scoop up a little bit of everything.

This recipe has a couple of genius twists, and the first is how the vegetables are cooked. They are initially steamed in a little bit of water along with salt, pepper, and thyme. This helps soften the vegetables just enough so when the final dish comes out of the oven, they are perfectly al dente.

And that flavor-infused cooking liquid does not go to waste—through the steaming process, you have essentially created your own vegetable broth that’s then used to dilute the cream of mushroom soup for the sauce.

Grandma’s Unique Topping

The other genius twist in this recipe is the delightfully crispy topping. There’s not a fried onion in sight here. Instead, the herbaceous crunch comes from crushed Rice Chex cereal.

All you have to do is scoop the cereal into a zip-top bag and give it a series of whacks with a mallet or roll over it a few times with a rolling pin. (Of course, that year, my grandma had to execute this step as well, lest someone else crush the cereal wrong!)

This Thanksgiving, I think I will give my three-year-old daughter a chance to participate in the preparations and put her in charge of this task. She will love it, and it gives me a chance to tell her a little bit about her great-grandma while we cook together.

The cereal is then lightly toasted in a pan with melted butter and tossed with thyme and onion powder. I love how this recipe doesn’t skimp on the topping. There is a nice layer to cover the entire surface of the baking dish and every bite comes with that important crunch.

Make It a Meal

Creamy Vegetable Casserole with Crunchy Chex Topping

Prep Time 15 mins

Cook Time 45 mins

Total Time 60 mins

Servings 6 servings

Keep Screen Awake

4 tablespoons unsalted butter, plus more softened butter for greasing baking dish
3 medium carrots, peeled
6 ounces green beans, ends trimmed
4 stalks celery plus 1 tablespoon finely chopped celery leaves
3/4 cup water
3/4 teaspoon salt
1/4 teaspoon freshly ground black pepper
1 teaspoon ground thyme
1 (10.5-ounce) can cream of mushroom soup
3 cups Rice Chex cereal
1/2 teaspoon onion powder

Preheat the oven to 350°F.

Butter a 9x9-inch or 7x11-inch baking dish and set aside.
Prep and cook the vegetables:

Slice the carrots, green beans, and celery into small pieces, between 1/4 and 1/2-inch in size; you should have 1 1/2 cups of each chopped vegetable.

Place the vegetables, celery leaves, water, salt, pepper, and 1/2 teaspoon of the ground thyme in a saucepan. Bring to a boil, then reduce the heat to low and cover with a lid. Cook, covered, until fork tender, about 15 minutes.
Make the sauce and coat the veggies:

Using a slotted spoon, scoop the vegetables out of the saucepan and set aside in a bowl.

Transfer the liquid remaining in the saucepan to a measuring cup; there should be about 1/2 cup. If you don't have 1/2 cup, add water to reach that amount. Return the liquid to the pan, add the cream of mushroom soup, and stir to combine. Add the reserved vegetables back to the pan and stir to coat completely.

Spoon the mixture into the prepared baking dish and spread it out evenly. Set aside while you make the topping.
Make the topping:

Place the cereal in a zip-top bag and coarsely crush with a mallet or rolling pin. Melt the butter in a large skillet over low heat, then add the crushed cereal, the remaining 1/2 teaspoon ground thyme, and the 1/2 teaspoon onion powder to the skillet.

Cook the cereal over low heat for 5 minutes, stirring often to coat. Sprinkle the topping evenly over the vegetables in the casserole dish.
Bake:

Bake the casserole until bubbly, 25 to 30 minutes. Let cool for about 5 minutes, then serve warm.

Store leftovers in an airtight container in the refrigerator for up to 3 days.

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Nutrition Facts (per serving)
233	Calories
10g	Fat
31g	Carbs
5g	Protein

Nutrition Facts
Servings: 6
Amount per serving
Calories	233
% Daily Value*
Total Fat 10g	13%
Saturated Fat 6g	28%
Cholesterol 23mg	8%
Sodium 504mg	22%
Total Carbohydrate 31g	11%
Dietary Fiber 3g	10%
Total Sugars 4g
Protein 5g
Vitamin C 5mg	24%
Calcium 86mg	7%
Iron 1mg	5%
Potassium 275mg	6%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Nutrition information is calculated using an ingredient database and should be considered an estimate. In cases where multiple ingredient alternatives are given, the first listed is calculated for nutrition. Garnishes and optional ingredients are not included.